This section provides background information related to the present disclosure which is not necessarily prior art.
Emission regulation requirements are mandating that engines have exhaust after-treatment systems to eliminate, or at least substantially minimize, the emission of, for example, particulate matter and NOX. To eliminate or reduce the emission of particulate matter and NOX, exhaust after-treatment systems can include exhaust treatment components such as a particulate filter (e.g., a diesel particulate filter (DPF)), a selective catalyst reduction (SCR) component, and a diesel oxidation catalyst (DOC) component.
SCR and DOC components generally work in conjunction with reductant injection systems that inject a reductant into the exhaust stream to treat the exhaust before the exhaust enters the SCR or DOC components. In the case of SCR, a reductant solution including urea is injected into the exhaust stream before entry into the SCR component. In the case of DOC, a hydrocarbon reductant such as diesel fuel is injected into the exhaust stream before entry into the DOC component.
Due to packing constraints, exhaust treatment components such as the SCR component or DOC component can be irregularly shaped. Due to the irregular shape of the exhaust treatment component, it can be difficult to ensure a uniform dispersion of the reductant exhaust mixture over the entire surface of the catalyst-coated substrates of the irregularly-shaped exhaust treatment component.